Do not move mid point for simple arrows bound on both ends

packages/element/src/binding.ts

@@ -863,7 +863,10 @@ export const updateBoundElements = (
       ? elementsMap.get(element.startBinding.elementId)
       : null;
     const endBindingElement = element.endBinding
-      ? elementsMap.get(element.endBinding.elementId)
+      ? // PERF: If the arrow is bound to the same element on both ends.
+        startBindingElement?.id === element.endBinding.elementId
+        ? startBindingElement
+        : elementsMap.get(element.endBinding.elementId)
       : null;
 
     let startBounds: Bounds | null = null;
@@ -936,6 +939,9 @@ export const updateBoundElements = (
       ...(changedElement.id === element.endBinding?.elementId
         ? { endBinding: bindings.endBinding }
         : {}),
+      moveMidPointsWithElement:
+        !!startBindingElement &&
+        startBindingElement?.id === endBindingElement?.id,
     });
 
     const boundText = getBoundTextElement(element, elementsMap);

packages/element/src/linearElementEditor.ts

@@ -1426,6 +1426,7 @@ export class LinearElementEditor {
     otherUpdates?: {
       startBinding?: PointBinding | null;
       endBinding?: PointBinding | null;
+      moveMidPointsWithElement?: boolean | null;
     },
   ) {
     const { points } = element;
@@ -1471,6 +1472,14 @@ export class LinearElementEditor {
       : points.map((p, idx) => {
           const current = pointUpdates.get(idx)?.point ?? p;
 
+          if (
+            otherUpdates?.moveMidPointsWithElement &&
+            idx !== 0 &&
+            idx !== points.length - 1
+          ) {
+            return pointFrom<LocalPoint>(current[0], current[1]);
+          }
+
           return pointFrom<LocalPoint>(
             current[0] - offsetX,
             current[1] - offsetY,